Chuck



Patented Sept. 6,1921.

CHUCK.

APPLICATION FILED JULY 5,1919.

W. A. BARKER.

W g. A 2/ 7 4 7 W W. A. BARKER.

CHUCK.

APPLICATION FILED JULY 5,1919. 1,389,731. PatentedSept. 6, 1921.

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'to be used u UNITED, STATES PATENT OFFICE.

WENDELL A. BARKER, 0F EI 'JKHAIRT, INDIANA.

Specification of Letters Patent.

Patented Sept. 6, 1921.

Application flled July 5, 1919. Serial No. 308,888.

To all whom it may concern:

Be it known that I, WENDELL A. BARKER, a citizen of the United States,residing at Elkhart, in the county of Elkhart, State of Indiana, haveinvented certain new and useful Improvements in Chucks, of which thefollowing is a specification.

This invention relates to chucks adapted on lathes and the like, and hasreference chiefly to an improved mechanism for closing the work engagingjaws and holding them in gripping relation to the work.

. My present invention constitutes an improvement u on the subjectmatter of Letters Patent December 11, 1917, and is based upon the samebroad principle of operation as the device of said Letters Patent. Thedevice of this patent is characterized by the provision of means wherebythe chuck jaws may be readily forced into gripping engagement with thework by the simple manipulation of a hand lever while the chuck isrevolving at full speed as well as while it is standing still. In thesaid patent, however, the jaw operating mechanism is adapted to effect agripping movement of the jaws upon the work in the inward directiononly, being thus adapted for external gripping of the work alone. Oneobject of the present invention is to provide a mechanism designed andoperating upon the principle of my former patent, wherein the chuck jawsshall be adapted for and capable of both external and internal grippingof the work; in other words, whereby the jaws may be positively actuatedeither inwardly or outwardly into gripping engagement with the work.Another object is to improve upon the mechanism of my former patent inthe direction of reducing the effect of centrifugal force upon the jawoperating levers. Still another object is to improve the leverarrangement between the jaws and the lever operating cam, whereby a morepowerful leverage action upon the jaws is obtained.

My present invention, its mode of opera-' 0. 1,249,300, granted to me.

workable embodiment of the invention, and wherein,-

Figure 1 is a longitudinal sectional view through a chuck embodying myinvention, taken on the line 11 of Fig. 2, looking to the left of thelatter figure;

Fig. 2 is a transverse sectional view on the line 22 of Fig. 1, lookingto the right;

Fig. 3 1s a transverse sectional view taken pigtthe line 33 of Fig. 1,looking to the Fig. 4 is a transverse sectional view taken ifli t theline 44 of Fig. 1, looking to the Fig. 5 is a sectional detail on theline 55 of F g. 1, looking downwardly;

Fig. 6 18 a sectional detail on the line 6 6 of Fig. 1, lookingdownwardly.

Fig. 7 is a sectional detail on the line 7-7 of Fig. 5.

Referring to the drawings reference character 5 designates the hollowhub of a chuck body which is designed to be mounted .upon the spindle(not shown) of a lathe or like machine in a manner well understood. In aseries of radially arranged grooves 6 formed in the front face of thechuck body are mounted a plurality of gripping or work-holding jaws,each comprising inner andouter jaw base members 7 and 8 adjustablelengthwise relatively to each other by means of a jaw screw 9, and a jawproper 10 of the reversible step jaw type secured to the outer jaw basemember 8 by screws 11 and 12. This construction of chuck jaw is old andwell known in the art, except as to a friction device for preventing.accidental turning of the 'aw screw 9 hereinafter described, and urtherdetailed description thereof is unnecessary to an understanding of thepresent invention.

On the rear side of the inner jaw base member 7 is a square rearwardlyprojecting tenon 13 that lies within a rectangular slot 14 (Fig. 7)formed in a disk 15 that is rotatably seated in a circular bearingsocket 16 formed in one side of a lever arm 17. This lever 17, of whichthere are three in the instance shown, is fulcrumed at one end on afulcrum pin 18 (Fig. 5) extending through the chuck body, while itsother end carries a cam follower in the form of a roller 19 journale'don a laterally projecting pin 20. It will thus be seen that the pin orrotatably mounted a cam which, throu h slots or grooves 23 engagementwith the cam followers 19 of t e several levers. 17, is adapted tosimultaneously actuate all of said levers to force the chuck jaws eitheroutwardly or inwardly into gripping engagement with the work. This camcomprises a sleeve or collar 21 joumaled on the hub 5 and formed withanintegral annular flange 22, in the forward face of which are threesymmetrical cam cam rollers 19 travel. It will be-observed by referenceto Figs. 2 and 4 that each of these cam slots is formed with arelatively abrupt outward bend 24 at one end and a relativel abruptinward bend 25 at the other en The lever-actuating cam above describedis geared to mechanism very similar to that shown in my former patent,above identified, for causing the cam member to rotate with the chuckbody and to be partially rotated relativel to the chuck body to close or0 en the chuck jaws when the chuck is rotate or is standing still. Onthe cam sleeve 21 is formed a gear 26 (Fig. 3). A gear 27 of the samesize and number of teeth is rigidly secured by a key 28 or othersuitable means to the outer end of the chuck hub 5 so as to rotatetherewith. The gear 27 has a sleeve extension 29, on which and on thecam sleeve 21, just forwardly of thegear 26, is rotatably mounted a gearcage comprising 'a pair of rings 30 and 31 integrally spaced andconnected by crossbars 32 (Fig. 3). In this gear cage are mounted onpins 33 four pairs of planet gears, each pair consisting of a gear 34meshin with the gear 27 and a gear 35 meshing wit the cam gear 26, saidgears 34 and 35 being independently j ournaled side by side on thebearing pin 33. 36 designates a stationary annular rear wall, the innerperiphery of which fits over a short hub 37 on the cage ring 30. Theouter periphery of the stationary wall 36 is formed as a forwardlyextending flange 38 on which is formed an internal car 39 meshing withthe planet gears 34. ounted with capacity for a turning movement on theflange 38 and on the outer periphery of the cage ring 31 is a ring 40provided on its upper side with a radiall projecting handle 41 (Fig. 3)by which sai ring can be manually turned in either direction. On theinner periphery of the ring 40 is an internal gear 42 of the same sizeand number ofteeth as the internal gear 39 and that meshes with theplanet gears 35.

Fig. 4) in which the- An annular clamping nut or rin 43 ma be threadedonto the rear end of t e chuc hub 5 to prevent accidental escape of thekey 28 and to assist in uniting the parts and steadying theconstruction. Assumin now that the chuck is rotating, the gear 2 will berotated with the hub 5 of the chuck and by reason of the intermeshingrelation of the p anet gears 34 with the rotating gear 27 and thestationary internal gear 39, the gear cage will be rotated in the samedirection as the chuck but at a slower speed. As the gear cage rotates,carrying with it the planet gears 35, each of which meshes with the camgear 26 and'the internal gear 42 which normally is stationar relativelto the internal gear 39, the cam s eeve will e rotated in the samedirection as the chuck and at the same speed. Since the jaw operatinglevers 17 are carried by the chuck body and the cam sleeve is rotatingin the same direction and at the same speed as the chuck body, it willbe manifest that no relative movement between the cam ring and thelevers takes place, and consequently the jaws will remain stationaryrelativel to the chuck body. Assuming that the c uck jaws are open andthat the chuck is rotating in a clockwise direction, viewing Fig. 2, anda counter-clockwise direction viewing Figs. 3 and 4, with the camfollowers 19 lying in the outwardl turned ends 24 of the cam slots 23,should it be desired to close the jaws upon a piece of work, the handle41 is swung by the operator in a counter-clockwise direction, viewingFig. 3, carrying with it the movable internal gear 42 which, actingthrough the planet gears 35, will retard the rotation of the cam gear 26and cam ring, causing a relative rotation of these latter in a directionopposite to the direction of rotation of the chuck body. This causes thecam followers 19 to first pass out of the abrupt outwardly turned ends24 of the cam grooves, causing a rapid approach movement of the jawsonto the work. The cam followers travel through the intermediategradually inclined portions of the cam grooves, effecting a powerfulsqueezing or clamping action of the jaws upon the work, the handle 41being released and the movement of the ring 40 intermitted' as soon asthe jaws have firmly clamped the work, at which time .the cam followerswill have traveled to approximately the abrupt inwardly turned ends ofthe cam grooves. The jaws are released by swinging the hamdle lever 41in the opposite direction, in an obvious manner.

Similarly, if the work is to be internally gripped or clamped, the jaws10 are reversed from the position shown in Fig. 1, and, with the camfollowers lying in the abrupt inwardly turned ends 25 of the camgrooves, the handle lever 41 is swung in a clockwise direction, viewingFig. 3, carrying with it the movable internal gear 42, and this, actingthrough the planet gears 35, imparts an additional partial rotation tothe cam ring rela tively to the. chuck body and in the same directionthat the chuck body is rotating. This causes a rapid outward movement ofthe chuck jaws as the cam followers pass out of the inwardly turned ends25 of the cam grooves; and thereafter the jaws are more graduallyclamped into the work as the cam levers swing slowly outwardly under thepowerful leverage afforded by the long slightly inclined intermediateportions of the cam grooves. It will thus be manifest that the chuckjaws can be closed for either external or internal gripping of the workby simple manipulation of the handle 41 irrespective of the speed atwhich the chuck may be rotating and also when the ,chuck may be idle.

It will be further observed that since each of the levers is held at oneend by its fulcrum pin and at its other end between the walls of the camgroove against outward movement under centrifugal force, the latter doesnot and cannot have any appreciable influence or effect upon themechanism. It will further be observed that in the present constructionI have substituted a lever of the second class for the lever of thefirst class disclosed in my former patent, above referred to, thereby,for a given total length of lever, obtaining a more powerful leverageupon the chuck jaws. It will further be observed that in the presentarrangement, the long arm of the lever follows its pivotal or fulcrumpoints with respect to the direction of rotation, rather than precedingit, as in the arrangement of my former patent, above referred to. This Ihave also found to be an advantage in respect to steadiness of operationand lessening of the effect of centrifugal force upon the lever arms.

Referring next to a feature of improvement which resides in a device forpreventing an accidental turning of the jaw screw, this is best shown inFigs. 1 and 6, wherein the circular head 50 of the screw is formed witha circumferential V-sha ed groove 51, in which is fitted a friction s pit ring 52 having radially projecting end portions 53 lying side by sideand held within a socket 54 formed in the jaw base member 8 justopposite the groove 51 of the jaw screw. The frictional grip of thisring on the jaw screw does not interfere with the adjustment or settingof the latter by a square tool entered in a correspondingly shapedsocket 55 in the upper end of the screw, as is usual; but it effectivelyholds the screw against accidental turning when the chuck is inoperation. This screw locking feature is not claimed herein, but formsthe subject matter of a divisional application, Serial No. 440,318,filed January 27, 1921.

It is believed that my invention, its mode of operation and advantageswill be readily understood from the foregoing without furtherdescription; and I also reserve all such variations and modifications inthe details of construction and arrangement herein illustratedanddescribed as fairly fall within the purview of the invention asdefined by the following claims.

I claim:

1. In a chuck, the combination of a rotatable chuck body, jaws movableradially therein, levers pivoted at one end on said chuck body andarticulated intermediate their ends to said jaws, cam means concentriowith said body and normally rotating at the same speed and in the samedirection with the latter and operating on said levers at their otherends to swing said levers in both directions, and means for rotatingsaid cam means relatively to said chuck body while the latter isrotating, to effect actuation of said levers.

2. In a chuck, the combination of a rotatable chuck body, jaws movableradially therein, levers pivoted at one end on said chuck body andarticulated intermediate their ends to said jaws, cam means sleeved uponthe hub of said chuck body and operatively engaging said levers at theirother ends to swing said levers in both directions, means normallyeffecting rotation of said cam means at the same speed and in the samedirection as said chuck body, and manually operable means for increasingor decreasing the speed of rotation of said cam means relatively to thespeed of rotation of said chuck body, whereby to actuate said levers.

3. In a chuck, the combination of a rotatable chuck body, jaws movableradially therein, levers pivoted at one end on said chuck body andarticulated intermediate their ends to said jaws, a cam ring rotatableon said chuck body and formed with cam grooves each having abruptoutwardly and inwardly turned portions at its ends respectively and arelatively long gradually inclined intermediate portion, cam followerson the other ends of said levers riding in said cam grooves, meansnormally effecting rotation of said cam ring at the same speed and inthe same direction as said chuck body, and manually operable means forincreasing or decreasing the speed of rotation of said cam ringrelatively to the speed of rotation of said chuck body, whereby toactuate said levers.

4. In a chuck, the combination of a rotatable chuck body, jaws movableradially therein and each formed with a rearwardly extending tenon onits base, levers pivoted at one end on said chuck body and each formedintermediate its ends with a circular bearing socket, a disk rotatablyfitted in each of said sockets and itself formed with an aperture toreceive said tenon and of greater width than the latter to permitarcuate movement of said tenon therein, a cam ring sleeved on said chuckbody and formed in one face thereof with cam grooves each having abruptoutwardly and inwardly inturned end portions and a relatively longgradually inclined intermediate portion, cam followers on the other endsof said levers riding in said cam grooves, means normally efiecting 10rotation of said cam r' at the same speed and in the same directlon assaid chuck body, and manually operable means for increasing ordecreaslng the speed of rotation of said cam ring relatively to thespeed of 15 rotation of said chuck body, whereby to actuate said 1 vers.

WENDELL A. BARKER.

